Needle-actuating mechanism for zigzag-stitch sewing machines



July 20, 1943 A. N. HALE 2,324,336

NEFDLE-ACTUATING MECHANIsM FOR ZIGZAG-STITCH SEWING MACHINES I Filed Nov. '27, 1941 s Sheets-Sheet 1 O'rthur' /7. H649 July 20, 1943. A. N. HALE 2,324,336

7 NEEDLE-ACTUATING MECHANISM FOR ZIGZAG-STITCH SEWING MACHINES Filgd Nov. 27, 1941 3 Sheets-Sheet 2 1 Uri/wrf'lHaLe ymmaw q' mm 'fi A. N. HALE July 20, 1943.

H NEEDLE-ACTUATING MECHANISM FOR ZIGZAG-STITCH SEW ING MACHINES Filed Nov. 27, 1941 3 Sheets-Sheet 3 Patented July 20, 1943 NEEDLE-ACTUATING MECHANISM FOR ZIGZAG-STITCH SEWING MACHINES Arthur N. Hale, Bridgeport, Oonn., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application November 27, 1941, Serial No. 420,630

Claims.

This invention relates to sewing machines such as zigzag and group stitching machines, the invention having for its primary object to provide a simple, compact and high speed actuating mechanism for transmitting endwise and lateral reciprocatory movements to one ormore needles.

Another object of this invention is to provide a multiple needle zigzag-stitch sewing machine with needle-actuating mechanism adaptable and conveniently regulatable for use in the production of a wide range of stitches.

' With these and other objects in view, as may hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter described in connection with the aceompanying drawings which illustrate a preferred embodiment of the invention and from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

In the drawings, Fig. 1 represents a vertical longitudinal section of the free end portion of the bracket-arm of a sewing machine containing the improved needle-vibrating mechanism. Fig.

2 is a front end elevation, partly in section, of

the bracket-arm head of the machine. Fig. 3 represents a vertical section of a portion of the bracket-arm and illustrating the left hand neerile-carrier devices partly in elevation and partly in vertical section. Fig. 4 is a generally horizontal section, viewed in top plan, of the machine bracket-arm, the section being taken through the axes of rotation of the bracket-arm cross-shafts and coaxially of the cross-head guide-members. Fig. 5 is a detail view in top plan of the needle-carrier brackets, the needlebars being shown in section. Fig. 6 illustrates, in perspective, the partly disassembled needlecarrier parts. Fig. 7 is a disassembled perspective of the separable parts of the needle-clamp carrier-bracket.

The sewing machine has a frame including a hollow bracket-arm I terminating at its free end in a head 2. Rotatably journaled in the bracket-arm I to extend lengthwise thereof is a horizontally disposed actuating shaft 3. One end of the shafts 3 carries a crank-disk 4 connected by a link 5 to the lateral stud of a collar 6 suitably clamped upon a needle-reciprocating bar I. The bar I is journaled for endwise reciprocation in vertically alined and stationary bearing-bushings 8 and 9 suitably secured in the bracket-arm head 2. Attached to the lower end of the needle-reciprocating bar 1, by a screw I0, is a cross-bar II provided in the oppositely directed arms thereof with apertures I2 which are transverse to the length of the cross-bar H.

Pivotally connected to the cross-bar I I are two needle-carrier brackets disposed abreast and of the same construction, a description of one of. said brackets applying equally to the other;

Pivotally disposed in each of the apertures I2 and inserted therein from the rearward side of the cross-bar II is a pivot-stud I3 extending forwardly from the upper endof a link. depending vertically from the cross-bar.:l I and dis-' posed substantially parallel to the needle-reaps rocating bar I. Extending rearwardly from the lower end of the link I4 is a pivot-stud I5 disposed in a horizontal aperture I6 provided in one member ll of a separable needle-carrier bracket. The bracket-member H has a split boss i8 clamped by a screw I9 upon the lower end of a vertically disposed needle-carrier bar 20. The front face of the bracket-member I'I has a recess 2I providing clearance for the link I4 between horizontally spaced bracket-member lugs Detachably secured to the bracket-member is a complemental bracket-member 23 having rearwardly extending and horizontally spaced lugs 24 which underlie the lugs 22 and are apertured to receive the attaching screws 25 threaded into the bracket-member H from the under side thereof. The lugs 24 of the complemental bracket-member 23 are preferably disposed in engagement with the opposite side 'faces' of a lug 26 depending from the bracket-member II, whereby the bracket-member 23 is more rigidly o secured to the bracket-member I'I.

The complemental bracket-member 23 has a forwardly extending and horizontally disposed upper flange 21 and a relatively narrower lower rib or flange 28; said flanges Z1, 28 providing therebetween a horizontal guideway in which a needle-clamp plate 29 is disposed for horizontal adjustment. The needle-clamp plate 29 is Dr?)- vided with a horizontally elongated aperture 30, through which passes the plate-securing screw 3| threaded into the bracket-member 23. I The clamp-plate 29 is provided in one end thereof with a vertical slot 32 to receive the shank of a needle 33 secured in the clamp-plate 29 by' a screw 34. The slotted end-portion of the clampplate 25 is preferably provided with a forwardly posed in the proximate ends of said clampplates, thereby providing for close approach to each other of said needles.

The flanges 27 of the respective bracket-members 23 are recessed in the upper faces thereof to form horizontally alined guide-grooves 36. Secured in the guide-groove 36 of one of the bracket-member flanges 21, by screws 31, is a steadying plate 38 which is slidably confined in the guide-groove of the adjacent bracket-- member. This arrangement provides for lateral movement of the individual needle-carrier brackets relatively to each other while, at the same time, restraining said brackets against angular movement about the vertical axes of the needlebars 20.

The left hand needle-bar 20 is journaled for endwise reciprocation in a vertically apertured guide-sleeve 39 which, in the present case, is integral with a horizontally reciprocatory crosshead 40 disposed within the bracket-arm head 2. The cross-head 40 has a rearwardly extending and horizontally flattened guide-rib 4| slidingly confined between vertically spaced and angular guide-plates 42. These guide-plates 42 extend inwardly through an opening 43 in the rear Wall of the bracket-arm head 2 and are secured, by screws 44, to said wall for vertical adjustment relative to each other.

The right hand needle-bar 20 is likewise journaled for endwise reciprocation in a vertically apertured guide-sleeve 45 integral with a horizontally reciprocatory cross-head 46 disposed in the bracket-arm head 2 adjacent to and at substantially the same level as the cross-head 46. The cross-head 46 also has a flattened, rearwardly extending rib 41 confined between rela tively adjustable guide-plates 48 similar to the guide-plates 42.

Forwardly of the guide-sleeve 45, the crosshead 46 is formed with a horizontally apertured split boss 49.. The cross-head boss 49 is clamped by a screw 50 upon one end of a longitudinally tubular sleeve 5| adapted to be endwise reciprocated horizontally cross-wise of the line of seam formation, i. e., the sleeve 5| is adapted to be reciprocated crosswise of the parallel paths of endwise reciprocation of the needle-bars 28. To this end, the sleeve 5| is slirlably journaled in a horizontally apertured bushing 52 suitably secured in a wall of the bracket-arm head 2. The sleeve 5| extends through said bushing 52 and, externally of the bracket-arm, the outer end of said sleeve 5| is provided with an upturned car 53 pivotally connected by a screw 54 to one end of a pitman 55. The pitman 55 extends through an opening 56 in the bracket-arm and, at its other end, has a strap 5! embracing an actuat ing eccentric 58.

The eccentric 58 is carried by a rotary crossshaft 59 disposed below and horizontally transverse to the arm-shaft 3; said cross-shaft 59 being rotatably journaled in the bracket-arm l. The eccentric 53 is. adjustable as to eccentricity and is constructed, in the present case, substan tially in accordance with the disclosure in the U. S. patent to C. F. Gray, No. 1,020,039, March 12-, 1912. The cross-shaft 59 carries a spiral gear 60 engaged by a smaller spiral gear 6| carried by the arm-shaft 3, the ratio of said gears 60 and Si in the present machine being such that the arm-shaft it rotates twice for each rotation of the cross-shaft 59.

The arm-shaft 3 carries another spiral gear 62 in mesh with a spiral gear 63 carried by a second cross-shaft 64 disposed substantially parallel to and at the same level as the cross-shaft 59. The cross-shaft 64 is also rotatably journaled in the bracket-arm l and, in the present case, rotates at one half the speed of rotation of the arm-shaft 3. It is to be understood however that the ratios of the gears 60, 6E and B2, 63 may be otherwise than one-to-two, as may be desired. The cross-shaft 64 carries an adjustable eccentric 65 similar to the eccentric 58; and embracing the eccentric 65 is the strap 66 of a pitman 5i extending through the -bracketarm opening 53.

At a point proximate to the pitman-ear 53 and externally of the bracket-arm head 2, the pitman 81 is pivotally connected by a screw 68 to an upturned ear 69 at one end of a horizontally disposed slide-bar 10. The slide-bar I9 is telescopically and slidably journaled for endwise reciprocation in the longitudinal bore of the tubular sleeve 5|, whereby the slide-bar 15 is nested in the sleeve 5| and has a horizontal path of reciprocation coaxially of said sleeve in a direction crosswise of the path of endwise reciprocation of the needle-bar 25. At its other end, the slidebar '50 is preferably additionally journaled in a bushing suitably secured in the front end wall of the bracket-arm head 2. Clamped upon the slide-bar 10 by a screw 12 is a split boss 73 at the forward end of the left hand cross-head 40.

In the operation of the machine, the work is advanced past the stitch-forming mechanism by a feed-dog l4 opposed by a presserfoot 15 attached to the lower end of the usual spring-olepressed presser-bar 16. As before explained, the two needles 33 are disposed abreast with respect to the direction of feed of the work. As the needles 33 are rigidly carried by the needle-bars 28 which are guided by the cross-head sleeves 39 and 45 for endwise reciprocation and for lateral to and fro movements in the same vertical plane, said needles are maintained vertical throughout their complete paths of movement.

Upon rotation of the armhaft 3, the bar 7 is reciprocated vertically, thereby transmitting vertically or endwise-reciprocatory movements in unison to the needles 33 by reason of the separate link connections i4 between the cross-bar of the needle-reciprocating bar I and the separate needle-carrier brackets. The links M permit the needle-carrier bars 2i! to move laterally with respect to their common reciprocating bar I and, as the links l4 are vertically disposed, the vertical reciprocations imparted to the laterally moving bars 29 is inconsequentially affected by reason of the link connections l4 within the limits of the lateral movements transmitted to said bars 20.

The needle-vibrating eccentrics 5B and 65 may obviously be timed to transmit to the needles 33 lateral movements which may be directionally in unison or opposed, as may be preferred. By adjusting on of the needle-vibrating eccentrics to zero eccentricity, one of the needles will be endwise reciprocated to make a straightaway line of stitches and the other needle may be endwise and laterally reciprocated to make zigzag stitches. Also, by relative adjustment of the eccentrics, zigzag-stitch seams of the same or of difierent widths selectively may be simultaneously produced by the two needles.

The needle-reciprocating bar I, as usual, has its path of endwise reciprocation in a vertical plane containing the axis of rotation of the armshaft 3. The abreast needle-carrier bar 20,

however, are so disposed that the paths of reciprocation of'said needle-carrier bars lie in avertical plane substantially parallel to and rearward of said vertical plane which contains the path of reciprocation of the needle-reciprocating bar.

This arrangement permits the employment of needle-carrier bar guides 39, 45, of sufficient lengths to adequately support the needle-carrier bars 20, without interference with the connections employed for actuating the needle-reciprocating bar I and without requiring undesirable enlargement of the head 2 of the bracket-arm. 9

Having thus set forth the nature of th invention what I claim herein is: l

1. In a zigzag-stitch sewing machine having a frame including a hollow bracket-arm, a laterally movable cross-head disposed within said bracketarm, opposed guide-elements carried by said bracket-arm and providing-therebetween a guideway for said cross-head, said cross-head having a guide-rib slidably disposed between said guideelements, securing means providing for varying the spacing from each other of said guide-elements, means for transmitting oppositely directed lateral movements to said cross-head, a needle-carrier bar journaled in saidcrcss-head for endwise reciprocation transversely of the path of movement of said cross-head, and means for r ciprocatingsaid needle-carrier bar.

2. In a zigzag-stitch sewing machine having a frame including a hollow bracket-arm, a laterally movable cross-head disposed within said bracket-arm, cross-head supporting means including a guide-member slidably extending from and journaled in said bracket-arm and guide-ele- 3.

head, means for transmitting oppositely directed lateral movements to said cross-head, a needlecarrier bar journaled in said cross-head for endwise reciprocation in a path disposed between said guide-member and guide-elements and extending transversely of the path of movement of said cross-head, and means for reciprocating said needle-carrier bar.

3. In a zigzag-stitch sewing machine having a frame including a hollowbracket-arm, a pair of laterally movable cross-heads disposed within said bracket-arm, telescopically arranged guidemembers extending from said cross-beach; in nested fashion through a wall of said bracketarm, actuating mechanism connected to proximate ends of said guide-members externally of said bracket-arm wall for actuating said crossheads, needle-carrier bars journaled in the respective cross-heads for endwise reciprocation transversely of the paths of lateral movement of the cross-heads, and means for endwise rec procating said needle-carrier bars.

4. In a zigzag-stitch sewing machine having a frame including a hollow bracket-arm, a pair of laterally movable cross-heads disposed within said bracket-arm, relatively movable cross-head guide-members extending in sliding engagement with each other through a wall of said bracketarm, one of said guide-members being journaled in said wall, means including connections with said guide-members externally of said bracketarm for actuating said cross-heads, needle-carrier bars journaled in said cross-heads for endwise reciprocation transversely of the paths of lateral movement of the cross-heads, and means for endwise reciprocating said needle-carrier bars. 5. In a 'zigzag-stitch sewing machine having a frame including a hollow bracket-arm, a pair of laterally movable cross-heads disposed within said bracket-arm, a tubular guide-sleeve extending from one of said cross-heads through a wall of said bracket-arm, said guide-sleeve being slidably journaled in said wall for endwise reciprocation, a guide-bar extending from the other of said cross-heads and slidably journaled for endwise reciprocation in said guide-sleeve, actuating mechanism connected to proximate ends of said guide-sleeve and guide-bar for trans mi-tting oppositely directed movements to said cross-heads, needle-carrier bars journaled in the respective crossheads for endwise reciprocation in-substantially parallel paths transverse to the paths of lateral movement of the cross-heads, a needle-reciprocating bar journaled for endwise reciprocation and disposed substantially parallel to said needle-carrier bars, means for actuating said needle-reciprocating bar, and operative connections with said needle-reciprocating bar for actuating said'needle-carrier bars. 6. Needle-actuating mechanism for zigzagstitch'sewing machines, comprising, a vertically disposed needle-reciprocating bar, means for endwise reciprocating said bar, a needle-carrier bar disposed adjacent and substantially parallel to said needle-reciprocating bar, a cross-bar extending laterally from the lower end of said needle-reciprocating bar; a link disposed substantially parallel to said needle-reciprocating bar and having o-ppo-siteends thereof pivotally con nected to said cross-bar and to said needle-carrier bar, and means for transmitting oppositely directed lateral movements to said needle carrier bar.

7. Needle-actuating mechanism for zigzag stitch sewing machines, comprising, a needlereciprocating bar, means for endwise reciprocating said bar, a needle-bar disposed adjacent and substantially parallel to said needle-reciprocating bar, a needle-carrier bracket attached to said needle-bar, a needle-clamp plate secured to said bracket for adjustment crosswise of said needle-bar, a link disposed substantially parallel to said needle-reciprocatingbar and having opposite ends thereof pivotally connected to said needle-reciprocating bar and to said needle-carrier bracket, and means for transmitting oppositely directed lateral movements to said needle-bar.

8. Needle-actuating mechanism for zigzagstitch sewing machines, comprising, a needle-reciprocating bar, means for endwise reciprocating said bar, needle-carrier bars disposed at opposite sides of and substantially parallel to said needle-reciprocating bar, a cross-bar carried by and having oppositely directed arms extending from said needle-reciprocating bar, links pivotally connected to the arms of said cross-bar and to the respective needle-carrier bars, said links being disposed substantially parallel to said needle-reciprocating bar, and means for transmitting oppositely directed lateral movements to said needle-carrier bars.

9. Needle-actuating mechanism for zigzagstich sewing machines, comprising, a needlereciprocating bar, means for endwise reciprocating said bar, endwise'and laterally reciprocatory needle-carrier bars disposed at opposite sides of and substantially parallel to said needle-reciprocating bar, connections with said nee- 10. Needle-actuating mechanism for zigzagstitching machines, comprising, a needle-reciproeating bar, means for endwise reciprocating said bar, a needle-bar disposed adjacent and substantially parallel to said needle-reciprocating bar, a bracket carried by one end of said needlebar and comprising separable bracket-members, a link having one end pivotally connected to said needle-reciprocating bar and having its other end pivotally connected to one of said bracket-members, needle-clamping means carried by the other of said bracket-members, and means for transmitting lateral movements in opposite directions to said needle-bar.

11. In a zigzag-stitch sewing machine, a pair of endwise and laterally reciprocatory needles, a rotary actuating shaft, connections with said shaft for endwise reciprocating said needles, a pair of auxiliary rotary shafts, operative connections with one of said auxiliary shafts for laterally reciprocating one of said needles, operative connections with the other of said auxiliary shafts for laterally reciprocating the other of said needles, and separate driving connections with said actuating shaft for rotating said auxiliary shafts in predetermined timed relation therewith.

12. In a zigzag-stitch sewing machine having a frame including a hollow bracket-arm, a pair of endwise and laterally reciprocatory needles, an actuating shaft rotatably journaled in and extending lengthwise of said bracket-arm, connections with said actuating shaft for endwise reciprocating said needles, a pair of substantially parallel auxiliary shafts rotatably journaled in said bracket-arm and lengthwise disposed transversely of said actuating shaft, rotary eccentrics carried by the respective auxiliary shafts, operative connections with one of said eccentrics for laterally reciprocating one of said needles, operative connections with the other of said eccentries for later-ally reciprocating the other of said needles, and separate gear connections with said actuating shaft for rotating said auxiliary shafts.

13. Needle-actuating mechanism for zigzagstitch sewing machines having a frame including a bracket arm, comprising, a needle-reciprocating bar journaled in said bracket-arm for endwise reciprocation, means for endwise reciprocating said bar, a laterally movable needle-bar guide, an endwise reciprocatory needle-carrier bar disposed substantially parallel to said needle-reciprocating bar, said needle-carrier bar being journaled in said guide rearwardly of said needle-reciprocatory bar, connections with said needle-reciprocating bar for actuating said needle-carrier bar, and means for transmitting oppositely directed lateral movements to said guide crosswise of the paths of reciprocation of said bars.

14. In a zigzag-stitch sewing machine having a frame including a bracket-arm, an actuating shaft rotatably journaled in said bracket-arm, a needle-reciprocating bar journaled for endwise reciprocation in said bracket-arm, crank-andlink connections with said shaft for endwise reciprocating said bar, a cross-head slidably disposed in said bracket-arm for movement cross- Wise of said needle-reciprocating bar, said crosshead having a guide-sleeve apertured transversely of the path of movement of said cross-head, a needle-carrier bar journaled for endwise movement in said guide-sleeve and disposed rearwardly of the path of reciprocation of said needle-reciprocating bar, connections with said needle-reciprocating bar for actuating said needlecarrier bar, and means for transmitting oppositely directed movements to said cross-head.

15. In a zigzag-stitch sewing machine having a frame including a bracket-arm, an actuating shaft rotatably journaled in said bracket-arm, a needle-reciprocating bar journaled in said bracket-arm for endwise reciprocation in a plane containing the axis of rotation of said shaft, a pair of cross-heads slidably disposed in said bracket-arm for movement crosswise of said needle-reciprocating bar, needle-carrier-bars journaled in the respective cross-heads and disposed adjacent each other in a plane rearward of and substantially parallel to the first mentioned plane, connections with said needle-reciprocating bar for actuating said needle-carrier bars, and means for reciprocating said cross-heads,

ARTHUR N. HALE. 

